927 resultados para HOMO-LUMO


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Lectins are a family of carbohydrate-recognition proteins which play crucial roles in innate immunity. In this study, a new lectin (CfLec-2) gene was cloned from Chlamys farreri by EST and RACE approaches. The full-length cDNA of CfLec-2 was composed of 708 bp, encoding a typical Long form carbohydrate-recognition domain of 130 residues. The deduced amino acid sequence showed high similarity to Brevican in Homo sapiens, C-type lectin-1 and lectin-2 in Anguilla japonica. The cDNA fragment encoding the mature peptide of CfLec-2 was recombined into plasmid pET-32a (+) and expressed in Escherichia coli Rosseta-Gami (DE3). The recombinant CfLec-2 (rCfLec-2) protein exhibited aggregative activity toward Staphylococcus haemolyticus, and the agglutination could be inhibited by D-mannose but not EDTA or D-galactose, indicating that CfLec-2 was a Ca2+ independent lectin. Moreover, rCfLec-2 could suppress the growth of E. coli TOP10F'. These results suggested that CfLec-2 was perhaps involved in the recognition and clearance of bacterial. pathogens in scallop. (C) 2007 Elsevier Ltd. All rights reserved.

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Apoptosis is an active process of cell death, which is an integral part of growth and development in multicellular organisms. The defender against cell death 1 (DAD1), the regulatory protein to inhibit the apoptosis process, was first cloned from the bay scallop Argopecten irradians by randomly sequencing a whole tissue cDNA library and rapid amplification of cDNA end (RACE). The full-length cDNA of the A. irradians DAD1 was 607 bp, consist of a 5'-terminal untranslated region (UTR) of 63 bp, a 3'-terminal UTR of 205 bp with a canonical polyadenylation signal sequence AATAAA and a poly (A) tail, and an open reading frame of 339 bp. The deduced amino acid sequence of the A. irradians DAD1 showed 75.5% identity to Araneus ventricosus, 74.5% to Drosophila melanogaster, and 73.6% to Homo sapiens, Sus scrofa, Mesocricetus auratus, Rattus norvegicus and Mus musculus. Excluding the Saccharomyces cerevisiae DAD1 homologue, all animal DAD1 including A. irradians DAD1 homologue formed a subgroup and all plant DAD1 proteins formed another subgroup in the phylogenetic analysis. The A. irradians DAD1 was expressed in all examined tissues including adductor muscle, mantle, gills, digestive gland, gonad and hemolymph, suggesting that A. irradians DAD1 is expressed in most body tissues. Furthermore, the mRNA expression levels of A. irradians DAD1 gene of hemolymph were particularly high after injury, suggesting that the gene is responsive to injury stimuli.

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A novel manganese superoxide dismutase (MnSOD) was cloned from bay scallop Argopecten irradians by 3' and 5' rapid amplification of cDNA ends (RACE) PCR. The full-length cDNA of MnSOD was of 1207 bp with a 678 bp open reading frame encoding 226 amino acids. The deduced amino acid sequence contained a putative signal peptide of 26 amino acids. Sequence comparison showed that the MnSOD of A. irradians shared high identity with MnSOD in invertebrates and vertebrates, such as MnSOD from abalone Haliotis discus discus (ABG88843) and frog Xenopus laevis (AAQ63483). Furthermore, the 3D structure of bay scallop MnSOD was predicted by SWISS-MODEL Protein Modelling Server and compared with those of other MnSODs. The overall structure of bay scallop MnSOD was similar to those of zebrafish Danio rerio, fruit fly Drosophila melanogaster, Chinese shrimp Fenneropenaeus chinensis, human Homo sapiens, and had the highest similarity to scallop Mizuhopecten yessoensis and abalone H. discus discus. A quantitative real-time PCR (qRT-PCR) assay was developed to detect the mRNA expression of MnSOD in different tissues and the temporal expression in haemocytes following challenge with the bacterium Vibrio anguillarum. A higher-level of mRNA expression of MnSOD was detected in gill and mantle. The expression of MnSOD reached the highest level at 3 h post-injection with V. anguillarum and then slightly recovered from 6 to 48 h. The results indicated that bay scallop MnSOD was a constitutive and inducible protein and thus could play an important role in the immune responses against V anguillarum infection. (c) 2008 Elsevier Ltd. All rights reserved.

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The inhibition effect of metal-free phthalocyanine (H2Pc), copper phthalocyanine (CuPc) and copper phthalocyanine tetrasulfuric tetrasodium salt (CuPc center dot S(4)center dot Na-4) on mild steel in I mol/l HCl in the concentration range of 1.0 X 10(-5) to 1.0 X 10(-3) mol/l was investigated by electrochemical test, scanning electron microscope with energy dispersive spectrometer (SEM/EDS) and quantum chemical method. The potentiodynamic polarization curves of mild steel in hydrochloric acid containing these compounds showed both cathodic and anodic processes of steel corrosion were suppressed, and the Nyquist plots of impedance expressed mainly as a capacitive loop with different compounds and concentrations. For all these phthalocyanines, the inhibition efficiency increased with the increase in inhibitor concentration, while the inhibition efficiencies for these three phthalocyanines with the same concentration decreased in the order Of CuPc center dot S(4)center dot Na-4 > CuPc > H2Pc according to the electrochemical measurement results. The SEM/EDS analysis indicated that there are more lightly corroded and oxidative steel surface for the specimens after immersion in acid solution containing 1.0 x 10(-3) mol/l phthalocyanines than that in blank. The quantum chemical calculation results showed that the inhibition efficiency of these phthalocyanines increased with decrease in molecule's LUMO energy, which was different from the micro-cyclic compounds. (c) 2005 Elsevier B.V. All rights reserved.

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Nine novel triazole compounds containing ester group were designed and synthesized. Their structures were confirmed by elemental, H-1 NMR and IR analyses, and optimized by means of DFT (Density Functional Theory) method at the B3LYP/6-31G* level. Based on the quantum-chemical calculation results and the Pearson coefficients between FA and quantumchemical parameters, V, LogP, MR and E-HOMO are shown to be the important relative factors which affect FA of the title compounds.

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RPLP1 is one of acidic ribosomal phosphoproteins encoded by RPLP1 gene, which plays an important role in the elongation step of protein synthesis. The cDNA of RPLP1 was cloned successfully for the first time from the Giant Panda (Ailuropoda melanoleuca) using RT-PCR technology, which was also sequenced, analyzed preliminarily and expressed in E. coli. The cDNA fragment cloned is 449bp in size, containing an open reading frame of 344bp encoding 114 amino acids. Alignment analysis indicated that the nucleotide sequence and the deduced amino acid sequence are highly conserved to other five species studied, including Homo sapiens, Mus musculus, Rattus norvegicus, Bos Taurus and Sus scrofa. The homologies for nucleotide sequences of Giant Panda PPLP1 to that of these species are 92.4%, 89.8%, 89.0%, 91.3% and 87.5%, while the homologies for amino acid sequences are 96.5%, 94.7%, 95.6%, 96.5% and 88.6%. Topology prediction showed there are three Casein kinase II phosphorylation sites and two N-myristoylation sites in the RPLP1 protein of the Giant Panda (Ailuropoda melanoleuca). The RPLP1 gene was overexpressed in E. coli and the result indicated that RPLP1 fusion with the N-terminally His-tagged form gave rise to the accumulation of an expected 18kDa polypeptide, which was in accordance with the predicted protein and could also be used to purify the protein and study its function.

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The identification of six synthesized diosgenyl saponin analogs with up to five sugars was accomplished by NMR studies. A combination of homo- and heteronuclear two-dimensional NMR techniques was utilized to achieve the complete H-1 and C-13 NMR assignments. Copyright (C) 2000 John Wiley & Sons, Ltd.

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Homo sapiens, gatu­nek nie­mal pod każ­dym wzglę­dem jed­no­rodny fizjo­lo­gicz­nie, pod­dany pra­wie jed­na­ko­wym pro­ce­som bio­lo­gicz­nym i spo­łecz­nym, o podob­nej ewo­lu­cyj­nej prze­szło­ści; gatu­nek, który poro­zu­miewa się tysią­cami róż­nych języ­ków. Ludzie są iden­tycz­nie zbu­do­wani, ale nie posłu­gują się jedną, uni­wer­salną mową. Korzy­ści, jakie wyni­ka­łyby ze wspól­nego, zro­zu­mia­łego dla każ­dego czło­wieka języka, są oczywiste. Tęsk­nota za takim języ­kiem jest obecna we wszyst­kich cywi­li­za­cjach. Wątek pomie­sza­nia języ­ków (The Con­fu­sion of Ton­gues), rekon­struk­cja i kon­struk­cja języka dosko­na­łego snuje się przez wszyst­kie kul­tury. W mito­lo­gii wie­lość języ­ków to nie­szczę­ście i sła­bość ludz­ko­ści. Sta­ro­żytni Per­so­wie wie­rzyli, iż wie­lo­ję­zyczny ród czło­wie­czy doczeka się w końcu wspól­nego języka w kró­le­stwie Ormuz­do­wym.

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Celem artykułu jest nakreślenie możliwych kierunków badań w zakresie analizy dyskursu i szerzej pragmalingwistyki. Służy temu wyodrębnienie najważniejszych relacji komunikacyjnych zachodzących w klasycznych grach fabularnych (ang. Role-Playing Games), a także wskazanie zbieżności zachodzących pomiędzy relacjami uczestników techniki gier fabularnych jako komunikacyjnej techniki nauczania języków obcych a założeniami autonomizacji glottodydaktyki na poziomie akademickim, związanymi z ideą współpracy dydaktycznej i relacji wielopodmiotowej.

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„Dziś jego postawa zapiera dech. Dać żyjącym exempla...”, powiada Paul Veyne w eseju Ostatni Foucault i jego moralność, i powiada tak o Foucault, ale gdy się nad tym zastanowić, w tradycji filozoficznej można odnaleźć cały ciąg postaci, które w pewnych okresach życia pragnęły jednego - właśnie chciały „dać żyjącym exempla”. Takim przykładem wśród jeszcze nie piszących filozofów mógłby być Sokrates. Tacy byli cynicy, a zwłaszcza bodaj najgłośniejszy z nich, Diogenes. Tacy wreszcie byli i stary Kant, i stary Nietzsche. Ich życie i ostatnie dzieła to często swoiste podręczniki życia, jednak nie tyle zobowiązujące powszechnością i obiektywnością wypowiadanych twierdzeń, co raczej przekonujące subiektywnością i jednostkowością przykładu. Każdy z nich, na swój sposób, dawał przykład jako filozof. Filozofował, dając przykład — swoim życiem, swoim dziełem. Czasami i jednym, i drugim. Istnieje grono filozofów, których życie było niezwykle blisko związane z działalnością filozoficzną, u których często trudno oddzielić filozofię od życia, u których konstytuuje się (Foucaulta) „ethos, filozoficzny sposób życia.” Sokrates, który nie ucieka przed sądem, choć może, i nie unika śmierci, choć może; Diogenes, kochany przez Ateńczyków skandalista, o którym Żywoty i poglądy słynnych filozofów powiadają, że „w byle jakim miejscu załatwiał wszystkie swoje sprawy”; Kant, który przez całe życie wstaje dokładnie o 4:55 na hasło swojego sługi, Lampego, Es ist Zeit, Herr Professor! i którego przechadzki po Królewcu mogą zastępować wskazania zegara; Nietzsche kończący w Turynie Ecce homo, jakby w przewidywaniu zbliżającej się katastrofy; i wreszcie umierający na AIDS i gorączkowo poprawiający na szpitalnym łóżku ostatnie dwa tomy Historii seksualności Michel Foucault (pytanie o splot jego własnego życia z ostatnim fragmentem jego dzieła jest pytaniem niezwykle trudnym, a odpowiedzi nie są jednoznaczne). Można by powiedzieć, iż każdy z nich pragnął wzmocnić swoją filozofię przykładem swojego życia. Asceza Kanta jest przecież nieodłączna od jego etyki, „troska o siebie” Foucaulta jest nieodłączna od jego „estetyki egzystencji”, śmierć Sokratesa i Nietzschego odejście od świadomego życia jedynie wzmacniają moc ich filozoficznych i etycznych wyborów (można by wręcz zastanawiać się, co stałoby się z Sokratesa „przykładem”, gdyby zdecydował się na ucieczkę z Aten, podobnie z myślą Nietzschego, gdyby, jak Hegel pod koniec życia, jedynie grał w karty...). Kant w trzeciej części Sporu fakultetów, Nietzsche w Ecce homo, Foucault w ostatnich częściach Historii seksualności (i pracach ją dopełniających), poza wszystkim innym, dają siebie za przykład: nie tyle od razu i po prostu wart naśladowania, lecz właśnie na początek jedynie wart przemyślenia. Paradoksalnie, to właśnie w ostatniej pracy Kanta i ostatniej pracy Nietzschego ich życie splata się z dziełem w jeden węzeł, to książki pisane własną krwią (jak powiedziałby Bataille, uważny czytelnik Nietzschego), własnym życiem.

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UNLABELLED: Newly discovered fossil assemblages of small bodied Homo sapiens from Palau, Micronesia possess characters thought to be taxonomically primitive for the genus Homo. BACKGROUND: Recent surface collection and test excavation in limestone caves in the rock islands of Palau, Micronesia, has produced a sizeable sample of human skeletal remains dating roughly between 940-2890 cal ybp. PRINCIPLE FINDINGS: Preliminary analysis indicates that this material is important for two reasons. First, individuals from the older time horizons are small in body size even relative to "pygmoid" populations from Southeast Asia and Indonesia, and thus may represent a marked case of human insular dwarfism. Second, while possessing a number of derived features that align them with Homo sapiens, the human remains from Palau also exhibit several skeletal traits that are considered to be primitive for the genus Homo. SIGNIFICANCE: These features may be previously unrecognized developmental correlates of small body size and, if so, they may have important implications for interpreting the taxonomic affinities of fossil specimens of Homo.

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MAPKKK dual leucine zipper-bearing kinases (DLKs) are regulators of synaptic development and axon regeneration. The mechanisms underlying their activation are not fully understood. Here, we show that C. elegans DLK-1 is activated by a Ca(2+)-dependent switch from inactive heteromeric to active homomeric protein complexes. We identify a DLK-1 isoform, DLK-1S, that shares identical kinase and leucine zipper domains with the previously described long isoform DLK-1L but acts to inhibit DLK-1 function by binding to DLK-1L. The switch between homo- or heteromeric DLK-1 complexes is influenced by Ca(2+) concentration. A conserved hexapeptide in the DLK-1L C terminus is essential for DLK-1 activity and is required for Ca(2+) regulation. The mammalian DLK-1 homolog MAP3K13 contains an identical C-terminal hexapeptide and can functionally complement dlk-1 mutants, suggesting that the DLK activation mechanism is conserved. The DLK activation mechanism is ideally suited for rapid and spatially controlled signal transduction in response to axonal injury and synaptic activity.

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A series of poly(N-isopropylacrylamide) [pNIPAM]-based homo-polymer and co-polymer microgel particles were prepared by surfactant-free emulsion polymerisation. The co-monomers were acrylic acid. 4-vinylpyridine. butyl acrylate, 4-vinylbiphenyl and vinyl laurate. Co-monomers were added at a concentration of 10% (w/w) relative to the base monomer pNIPAM for the preparation of each co-polymer microgel. The co-monomers chosen vary by their organic chain length, polarity and pH sensitivity, as these should influence how the particles behave in aqueous and non-aqueous solvents. The effect of adding different types of co-monomer into the microgel structure was investigated with respect to their dispersibility in different solvents. These microgel particles have shown useful application in the removal of water from biodiesel prepared from rape seed. Karl Fischer experiments showed that microgel particles can be used to reduce the water content in biodiesel to an acceptable level for incorporation into internal combustion engines. (C) 2008 Elsevier B.V. All rights reserved.

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Theatre is a cultural and artistic form that involves a process of communication between creators and is received in a space and time located in the public sphere, which has meant that, over the centuries, it has acted as a space for expression, exchange and debate regarding all manner of ideas, causes and struggles. Implicit within this process are processes of expression, creation and reception, by way of which people demonstrate, analyse and question ways of seeing and understanding life, and ways of being and existing in the world. This gives rise to educational, cultural, social and political potential, which has been endorsed in numerous studies and investigations. In this work, in which theoretical orientation is established through a review of the relevant literature, we consider different intersections that occur between theatre and social work in order to also show that dramatic and theatrical expression offers substantive methodologies for achieving some objectives of social work, particularly in areas such as critical literacy, reflexivity and recognition, awareness raising, social participation, personal and/or community development, ownership of cultural capital and access to personal and social wellbeing.

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In this paper we study the response in time of N2, O2, and F2 to laser pulses having a wavelength of 390 nm. We find single-ionization suppression in O2 and its absence in F2, in accordance with experimental results at lambda= 800 nm. Within our framework of time-dependent density functional theory we are able to explain deviations from the predictions of intense-field many-body S-matrix theory (IMST). We confirm the connection of ionization suppression with destructive interference of outgoing electron waves from the ionized electron orbital. However, the prediction of ionization suppression, justified within the IMST approach through the symmetry of the highest occupied molecular orbital (HOMO), is not reliable since it turns out that—e.g., in the case of F2—the electronic response to the laser pulse is rather complicated and does not lead to dominant depletion of the HOMO. Therefore, the symmetry of the HOMO is not sufficient to predict ionization suppression. However, at least for F2, the symmetry of the dominantly ionized orbital is consistent with the nonsuppression of ionization.